After the pandemic, I knew it was time to stop my big bike adventure and return to my mountain biking roots.
Today I will share with you how I optimized my bikepacking bicycle for my current backcountry adventures.
Even if your interest is not in mountain biking, or bikepacking, I will teach you about frame design, suspension setup, and how to tune a full suspension bike for maximum performance.
How did I get my long-travel enduro bicycle for bikepacking?
A Bikepacking Bicycle For A Specific Purpose
Oaxaca has the best gravity mountain biking in Mexico, and it is not exaggerated.
Sierra Norte is a mountain range that lies behind Oaxaca. It has over a dozen trails, with at least 1000m (3300ft), of elevation drop. The majority of trails are ancient tracks that were carved into the mountainside over thousands of years. They take you from one point to the next. These trails can be very steep, rocky, and loose.
My current mission is explore as many of these ancient routes as possible. I think an enduro bike is the best way to do so.
My Enduro Bike Criteria
Here are some requirements that I have set in order to help you choose a bike for technical, steep terrain.
Full-suspension bike, more than 160mm travel, to provide me with traction on the toughest trails.
A head tube angle between 63 and 65 degrees is recommended to ensure a long frontal length and good steering characteristics.
For steep climbs, my front wheel is kept planted at 78 degrees by the seat tube angle.
My long frame reach (510mm+), to accommodate my annoying arm span.
Dropper seatpost to allow me to place my body weight nearly anywhere between my front & rear tyres.
I received a stock alert on a bike (Nukeproof mega 290 Comp), so I bought it and it was shipped to Mexico.
Geometry for the Nukeproof Mega 290 Frame
Let’s first look at the Nukeproof Mega frame geometry. The Mega follows modern mountain bike design principles of ‘long-, low- and slack.
A bike that’s longer in the wheelbase, lower in the bottom bracket height and has a flatter head tube angle can be achieved by increasing its length.
1. You can lower your centre mass, which makes it more stable when riding on steep or rough terrain.
2. It increases your front angle making it difficult for you to pitch above the bars after hitting a root or rock.
3. Provides a high level of mechanical trail, which acts as an stabilizing force to straighten the steering after your front wheels have been removed from-line.
Nukeproof Bikes with this geometry has one drawback: it makes it harder to climb steep trails with tight turns and technical terrain. I do most of my climbing on fire roads.
Low head tube angles can cause a heavy steering feeling, which could make it seem like my 64-degree bike might be a little too difficult to handle. The truth is that I have an 800mm wide handlebar, which gives me ample steering leverage to overcome the low front tyre pressure, steering weight, and front bag weight.
All I need to do to get an idea of how leverage can help a slackbike handle well is to ride with my hands further inboard.
The downside of a slackbike is that you can also experience a lot more wheel flop. This is a destabilizing force which pulls your front wheel to one side or the other when you ride at slower speeds. Although steering leverage decreases this effect, it is still evident when I am climbing.
It’s surprisingly easy to climb due to the steep effective seat tube angle. This is because my center of weight is higher forward than most bikes’, so my front wheel does not want to lift up, even if I’m going up 15% inclines.
Let’s now move to suspension.
How I Optimised My Suspension
Mega’s travel is 170mm (6.7″) up front, and 160mm at the back (6.3″) It has both an air fork (6.7”) and a shock (6.3′”), which makes it more suitable for bikepacking. I can easily add and remove air according to whether I have any luggage.
The Mega is clearly designed for descending. The frame design makes it possible for the rear shock (low anti rise) to be very active when rear braking is applied. This is especially true when the shock travels far. This is a great feature for loose, bumpy terrain because it gives my rear wheels the most grip.
The rear shock is too active for me when I ride uphill. It bounces around a lot more than I like. The Mega does not have a compression lockout button on the shock, which would save you money.
Although it doesn’t sound very appealing, I have a solution!
I reduce the shock’s speed of return from an impact (rebound), which significantly dulls the suspension response. My shock does not travel too far when I ride fire road climbs in a high cadence. It’s a very effective way to go.
When it comes to decending, I am very happy with the sound of the shock damper. It’s very compatible with my bike and body weight. The shock is set very soft for loose terrain. It’s extremely responsive to bumps and helps increase traction. The trails are smooth and there aren’t many large gaps between the shocks, which could cause it to bottom out.
Although the fork’s performance is generally satisfactory, I think it could be even better. It was again used soft with no compression damping to ensure the best possible small bump compliance.
It is a little too deep into its travel, which I don’t like. Although it would sit higher with more compression damping, even one click can feel harsh on the repetitive, fast bumps.
A higher-end suspension damper would enable me to tune my fork more accurately (high speed compression adjustment). Rockshox has an upgrade kit for dampers that offers more tuning capabilities, so I might get one.
How I Optimised My Tyres
Because of the Oaxacan’s loose and scrambly trails, my tyres cannot be pushed into corners for extra grip as I would on well-maintained trails. This terrain requires tyres that have a more aggressive tread pattern and lower pressures.
My tyres can be more deformed when I have low pressures. This increases my contact patch and, therefore, ground grip. The front of my bike also has a lower effective spring rate which provides more grip for high-frequency bumps.
Lower tyre pressures can also improve grip. Your tyres play an important role in improving bump compliance. This will reduce the trail’s harshness for your hands, and your upper body. I can often drop over 1000 metres vertically in one run. Low tyre pressures help me reduce how fast or far my handlebars go over bumps. This helps to minimize arm and hand fatigue.
Schwalbe and I have teamed up to help me dial in my tyre setup.
As I was able to use lower pressures for increased grip and fatigue, I thought a 2.6″ wide tyre would work best on this loose terrain.
The Schwalbe Magic Mary front tyre was more aggressive than my outgoing 2.4′. tyre. However, it was not providing enough grip for me when I cornered hard on soft surfaces. Even at 11psi/0.8bar, this was happening in my front tire!
I was initially quite confused but I think I finally figured it out. The tread pattern of the tyre becomes too open when it is increased from 2.4’s to 2.6’s. I resolved my front grip issue completely by switching from a 2.4′” model with 15-16psi/1-1bar.
Schwalbe sidewalls have another interesting feature: they are extremely stiff. This offers more puncture protection, and prevents sidewalls from collapsing on hard corners. However, they are less comfortable than other tyres with the same pressures.
You can get an idea of the difference in the amount of ‘harshness” between my previous Michelin front Tyre and mine with nearly 50% more pressure (22psi instead 15psi). This means you’ll always have to play around with the pressure when changing tyre models.
The Schwalbe Big Betty is the rear tyre that I have settled on. I like the 2.6 inch version. I run it at 17-18psi. Schwalbe’s less aggressive models performed well on hardpack trails that were rockier and more rugged, but the Big Betty is what I choose when the surface becomes loose.
Ok, you might be hearing me complaining about my low tire pressure and wondering how I keep my tyres from rolling off my rims.
Tyre Inserts Benefits
To maintain low tire pressures, my bike has Schwalbe PROcore tyre-ins.
Procore is a separate mountain bike tyre that can be fitted into your mountain bike’s tyre. The inner tube can be used to either inflate the outer or inner tyre.
Tyre inserts protect my rims against impacts and prevent pinch flats. Instead of the rock hitting directly on my rim, the rock will bounce off the inner tube. I can lower my tyre pressures and get more grip, comfort, and control without having to worry about causing damage to my rims or getting flats.
Procore also puts outward tension on my tyres which locks the bead to rim. Prior to this system, my Michelin tires would ‘burp’ on rocky trails, causing small amounts of air pressure and sealant loss. Procore makes this impossible.
Procore also makes it easy to set up a tubeless system with a hand pump. I simply inflate the inner tube first. The outer tube is then seated to the rim using a small amount of compressed air.
Procore makes it simple to switch tyres, since the inserts have a much smaller volume than Cushcore foam inserts. This allows you to easily handle your tyres and get them on and off. With this system, I can change my tire just as fast as without inserts.
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